Screw press



March 1o, 1925'. 1,529,215

W. RUPPERT sREw PRESS 'v Filed July '7, 1924 l@ j,

Patented Mar. l0, 1925.

UNITED STATES WILHELM RUPPERT, F VIENNA, AUSTRIA.

SCREW PRESS.

Application led July 7,

To all whom t may concern:

Be it known that I,`WILHELu Rurrnnna citizen of the Republic of Austria, residing at Vienna, Austria, have invented certain new and useful Improvements in Screw Presses (for which I have filed applications in Austria July 4, 1923, Number A. 3,060*

23, and Germany July 6, 1923, Number R.

58,878), of which the following is a specification.

In friction screw presses having driving friction discs adapted to rock around axes at right angles to their shafts and cooperating with two driven friction discs on the screw spindle, one of which is operative in the upward movement of the screw spindle while the other is operative in its downward movement, the arrangement is such that each driven friction disc engaging with the driven discs moves from the centres of the latter towards their peripheries, whereby the speed of the screw spindle and of the driven friction discs increases as they approach the ends of their up and down movements. Therefore on reversing the movement of the screw spindle at the upper end of its stroke a considerable quantity of kinetic energy has to be compensated for by friction and this causes a considerable expenditure of power and a rapid wear of the leathering of the friction discs besides objectionable irregularities in the operation of the press. Moreover when two driving friction discs are used, the pressures of the driving discs on the driven disc do not exactly counterbalance each other under such conditions and even one ofthe driving friction discs may become entirely inoperative in the downward movement of the spindle and the other in its upward movement. The required power is then not transmitted to the driven friction discs and the nut and screw spindle are rapidly' worn.

The object of my invention is to obviate these inconveniences.

With this object in view my invention consists in providing means whereby the pressure between the driving and the V driven friction discs is gradually reduced as the screw spindle moves upwards so that the 1924. serian No. 724,704.

driven friction disc vslips on the driving one to the greater an extent the more the screw spindle approaches the upper end of its stroke and thus the speed of the driven disc can rise only to a moderate value; furthermore in case of screw presses having two driving discs opposite each other I provide means whereby the pressures of the opposite drivingfriction discs on the driven friction discs are equalized.

In the annexed drawing Fig. 1 shows by way of example a front elevation of an embodiment of my improved friction screw press. Figs. 2, 3 and 4 are similarviews of modifications of the link and lever gearing connected with the ram for obtaining a variable transmission of pressure.

In the embodiment shown in Fig. 1 the two armed hand lever 1 pivoted at 2 in the frame of the press carries at one end a counter weight 3 tending to move downwards the controlling link 4 which is yieldingly connected by link and lever gearing to the driving friction discs 7 and 8 adapted to rock in opposite directions round pivot pins 5 and 6 at right angles to the common shaft of the discs 7 and 8 revolving in opposite directions. The arrangement is such that the driving friction discs 7 and 8 are forced against'the upperdriven friction disc 9 for screwing upwards the screw spindle on which the disc 9 is secured. When the screw spindle thusmoves upwards an arm 11 secured to the ram 10 gradually compresses a spring 12 interposed between this arm and a shoulder 13 on the link 4 whereby the pressure exerted by the counter weight 3 is progressively counter acted. Thereby 'the pressure between the driving discs 7 and 8 and the driven disc 9 is progressively reduced and in consequence thereof the disc 9 is not revolved with its full speed, but slips the more on the driving discs, the more the screw spindle approaches the upper end of its stroke. Therefore when the press is re versed the kinetic energy of the driven disc is comparatively small and will be readily overcome during a short movement of the screw spindle. I

The means providedA for reducing the pressure between the driving discs 7 and 8 and the driven disc 9 consist in the embodiment shown in Fig. 1 of a connecting plate 14 pivotally connected to the contro-lling levers 185 19 20 at 15, 16 and 17 respectively. By means of this connecting plate 14 the two drivingy discs 7 and' 8 areI reliably brought into contact with the drivenv friction discs 9 and 21 even if the drivingd-iseswere not exactly adjusted,:thepressureU-be.

tweenboth driving discs 7 and"8 and the driven disc 9 or 21 being equalized.

In the embodiment'i'shown in Fig. 2 the reduction of the pressurebetween .the-driving.; and the driven discs when the screw spin-v dle. approaches `.the upper fend Aof. xlits stroke is brought tabout in `the following`I .manner When the fram k102 rises the :counterweig'li't :3i is .1 moved. .towards the..fu1cru1n -fof the hand. lever 1 as `shown in. Fig.. 21 to* thel right, .by means off a: belli crank-lever 28 fulcrumedsat- 27 .in-fthe .'.fr'ameiof the press and engaging by one..0- 1its fbifurcated` farms a pin 29S-'oni the ram and1 L by 1 its z other biiurcated.V i arm. the counterweight 3 slidably. mounted"y on@ the hand. lever-.1:

Inithe embodiment .shown inFig..3 a.lever 22'is1piv0ted at 28 intheframe or' thepress, this lever Zis actuated by va pin.24son-the.ram engaging. into aslo't'thereof.A The ifree end` ofthele've-r 22 is pivotal-ly connectedf-toa sleeve 25 guided. on. the llinksafl which in/turn. engages xby pin andfslot :connection withv the contrclling lever 18.I Thusywhencthe ra-m rises the. linkiiisfsoyturned round` its vpivot ontliefhand rlever 1,1 as show-.n inrFigg 3 to thefright thatthe, operativeflength Vot, the arm cf^tliedlevver18 connectedtothe-said link/i yis the more reduced the more the screw` spindlelA approachestheuppenend Yoffits stroke, whereby j the pressure between.rthe.v drivingl discs andltlie drivendisc is reduced. By `shorteningthe operativeY length vof :the arm of-thelever 18.-als`o the leverage of the reversing-gear isadvantagecusly changed, as4 when the .1 operative VVlength; of this arm, '.,is shorter.; the .movement of thefram 10 during the reversing;- is likewise@shortened.iv The surplusfrotationof the driven?` frictionv disc` istherefore notfonly reduced` lby ...the reduction of. its kinetic energy ibut also bythe `ref ductioubf the, movement. L required Vfor re-- versing fthe. press.

In i Ythe. embodiment cshown :in v 1 Figi-1; ir VanV arm; 26:'.secured ,to the ram: 10 engages-with the link Land Ica-uses; tlie .outerend; of. this link to approach .f ,progressively pthe fulcrum of:HV the.cont-rolling;V lever 18 as thea screwspindle approaches-.fthe upper. end; ot f; its stroke;A otherwise, the arrangement;l andthe operation 1 are .the samel AasA ,describedv4- with reference Y to. Fig.;l 3.

OfV course as the screw spindle-.approaches the lower end of its stroke the pressure-beltween-thexdriving discsxf and-8 andfthe driven disc increases in all cases whereby the pressure or blow of the ram on the blank are increased.

I wish to be understood that I do not limit myself to the details of construction hereinbefore described as these may be varied within wide limits without departing `from theessence'of myinvention. 'i

IVhatI claim is:

`1. InV-a-friction .screw press in combination with a screw spindle carrying a rain, a pairof driven discs arranged to drive the screw spindle a pair of driving `friction discs rctatablevoni'fawcommon axis in opposite directions, arranged on opposite sides of the driven discs, and. adapted to :engage: there-i with', means :tor-V rocking-y t'h'e driving i discs on pivots :at right angles'l'to. the common* axis othe driving. discs, means actuated by. the Vscrew :spindle and actuatingfin turn ther saidwineansior Arocking the drivingcdiscsf. whereby the pressure `between the.` driving. discs and. Ithe .driven 5'discs is progressively increased and .reduced fas the screw spindley approaches the lower and upper end' respecf' tivelyiof fits stroke.` p

2. In a yfriction screwpress,.inz.combina-. tion= ywith a `.screww spindle :carrying arram; apailr 'oi driven. frictionfdi'scs securedto the screw.V spindle',y a pair: of# driving` friction: discsl rotatablefon acommonilaxis :in zoppo-1 site directions... arranged on opposite sides of the driven: discs .andcadapted lto :engagetherewith; and. meansOr rockingrthe. Ifdrivl'- ing discs `on pivotsat right anglestothel 100 common. axis offthezdrivingf discsf means actuated by the said.screw..spindleeandiactue ating yin yturn the .said means vdi'or. :rocking the driving discs,v whereby .the pressure between the driving discs. and.ithewdrivensdiscs-I isV 105 progressively increased. .and :reduced .as the screw. spindle approachesl the. lower: and. upper endi'respectiyely:et its strokefthe said. means .actuatech fby the s screw spindle.- comf;y prising, a levers andapin engaging: with 110 the: lever Aand.adapted to be shiftedl alongthel leverby vthe 'screw` spindle.;l

3.. Inra friction-.screw press.incombination with a screwrspindle carrying; amamhafpair of; driven, friction:v discs. secured 1' to the 115 spindle,V a p air -cif driving fricti1onidiscs l`ro'-` tatablel on: a commonl axis-.finropposite .'direcf tionsarrangedon: opposite sides f1 of the. driven Ydiscs and. adaptedto engage: *ftheree with` and .means'ffor rocking the .fdriving 120 discs. on pivots'f `at righti'fanglesxto thefcomaf mon. axisfof the idrivingrdiscsTmeans.actua ated by the said screwr:spindlefand,actuating initurn the '.saidmeanslfor Xrockingethe ..dr;iving discs whereby the pressurebetweenthe 125 driving discs and the` driven Adiscs? isiprogressively increased andreducedv as.` thel screwy spindle approaches-the .lower and. upper .end

` respectively ci its; stroke,V such. meansactuated bygthe screwspindle comprising, driv-v ing dise levers for rocking the driving discs, a lever, e force exerting pin engaging therewith and adapted to be shifted along the lever by the screw spindle, and a, link pivotally connected to the lever and to the driving disc levers for rocking both of the driving discs.

In testimony whereof l have signed my name to this speciication.

WILHELM RUPPERT. l/Vitnesses JOSEF GURMANN, M. REEBS. 

